A typical network of resistances $$R_1$$ and $$R_2$$ shown below extends to infinity towards the right. The total resistance $$R_{\text{effective}}$$ of this network between points $$A$$ and $$B$$ is

A

$$R_{\text{effective}} = R_1 + \sqrt{R_1^2 + 2R_1R_2}$$

B

$$R_{\text{effective}} = R_2 + \sqrt{R_1^2 + 2R_1R_2}$$

C

$$R_{\text{effective}} = R_1 + \sqrt{3R_1R_2}$$

D

$$R_{\text{effective}} = R_1 + \sqrt{R_2^2 + 2R_1R_2}$$